It’s not as easy as vector A to B and B to A. All units have their weapon on the right rather than center. So it is more like vector Aright to B vs Bright to A. So you can sometimes have LoS for your weapon but not the enemy.
Then we’re not talking about LoS but LoF 
. Two different things, and still abusing faults of game design of fixed weapon position. Stepping out of cover and waiting to be shot apparently is just a boardgamish representation of simultaneous actions with 360 awareness and yet such exploits like the one with LoF are considered valid, non obvious, tactical opportunities that has nothing in common with boardgamish representation of things. It’s very convenient yet inconsistent explanation why things should remain unchanged, and it’s all about learning curve of dealing with design. I don’t buy it.
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